摘要 |
<p>Vincaminic acid derivatives of formula (A) <IMAGE> (A) useful in treating cerebral insufficiency, are prepared by reacting 1-ethyl-2,3,4,6,7,12-hexahydroindolo[2,3-a]quinolizine with the 2,4-DNP hydrazone of ethyl or methyl bromopyruvate followed by (i) reduction of the C=N bond and (ii) simultaneous cyclization with removal of the ketone-protecting group in either order.</p> |